<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    <script>
        var obj='{"name":"cheng","age":18}'
        /* 将json格式的字符串转为json */
        var parseObj=JSON.parse(obj)
        console.log(parseObj)
        console.log(JSON.stringify(parseObj))
    </script>
</body>
</html>